In recent years, latent heat type heat storage materials that utilize latent heat based on phase transition between solid and liquid, phase transition between crystal and amorphous, or phase transition of crystal polymorphism have attracted attention. One example of the utilization of a latent heat type heat storage material is an embodiment in which, in a residence, heat is stored in a latent heat type heat storage material in the night using nighttime power and the stored heat is utilized during the daytime as a heat source for various applications and the electric power consumption during the daytime is thereby saved.
As polymers that can be applied to latent heat type heat storage materials, there are known polymers that develop heat storage performance by emitting or absorbing latent heat through phase transition of side chains (Patent Documents 1 to 3). Patent Document 4 discloses a crystalline higher α-olefin copolymer including two or more types of higher α-olefin having 10 or more carbon atoms as a polymer having a main chain and long side chains.